Florence was the birthplace of the Italian Renaissance. Politically, economically, and culturally it was the most important city in Europe for around 250 years; from some time before 1300 until the early 1500s.
Florentines reinvented money in the form of the gold florin. This currency was the engine that drove Europe out of the “Dark Ages” a term invented by Petrarch, a Florentine whose family had been exiled to Arezzo. They financed the development of industry all over Europe, from Britain to Bruges, to Lyon, to Hungary. They financed the English kings during the Hundred Years War. They financed the papacy, including the construction of the papal palace in Avignon and the reconstruction of St. Peters and the Vatican when the papacy returned to Rome from the “Babylonian captivity”.
Dante, Petrarch, and Boccaccio pioneered the use of the vernacular, the use of a language other than Latin. In their case, Tuscan, which, because of them, became Italian. Because Dante, et al., wrote in Tuscan, Geoffrey Chaucer, who spent a lot of time in Northern Italy and who borrowed heavily from Boccaccio’s little stories, wrote in English. Others started writing in French and Spanish. This was the beginning of the end of Latin as a common language throughout Europe.
The Florentines, perhaps most notably Filippo Brunelleschi (1377-1466) and Leon Battista Alberti (1404-1472) invented both Renaissance and neoclassical architecture. These architectural styles revolutionised the way Rome, London, Paris and every other major city in Europe from Barcelona to St. Petersburg were built.